1. Field of the Invention
The present invention relates to a district heat supply plant controller for controlling operation of a district heat supply plant having a plurality of heat source devices and, more particularly, to a district heat supply plant controller capable of efficiently driving each of heat sources of a district heat supply plant.
2. Description of the Related Art
A large-scaled building or a block of buildings usually has a district heat supply plant for air conditioning of the entirety of the district. District heat supply plants are configured to prepare hot water and cold water by using heat pumps or other appropriate heat source devices, store them in heat storage tanks, and supply them to air conditioners or other thermal load devices whenever demanded. District heat supply plants using electric power as their power sources are configured to use night-time electric power or peak-cut driving for efficient operation, by generating and storing heat in the night, generating hot water and cold water and discharging the stored heat in the day time.
For efficiently driving a district supply plant in the aforementioned manner, one or more professional operators (plant operators) are indispensable. However, these professional operators are difficult to acquire and hold stably, and the personnel expenses for them are great. Therefore, unmanned driving is desired at least in the night, for example. Currently, a method for determining an operation plan of a district heat supply plant based on mathematical programming is typically used as a method for automatic operation reflecting operator's professional knowledge.
As explained above, district heat supply plants are automatically operated by obtaining their operation plans on the basis of a mathematical programming and by reflecting operator's professional knowledge. Mathematical programming, however, tries to strictly obtain an optimum solution, and often results in finding no practical solution or determining an inappropriate solution due to an inappropriate modeling. Therefore, it is difficult to realize completely unmanned operation by mathematical programming. Additionally, when a district heat supply plant is enlarged in scale, the amount of calculations for determining an operation plan increases, and it is difficult to determine the operation plan within a service time.
To overcome these defects of mathematical programming, researches and studies have been started recently on an approach for obtaining operation plans of various kinds of plants by using genetic algorithms to obtain quasi-optimum solutions in a short time.